Field of Invention
The current invention relates to an apparatus and method for improving jack lubrication by providing a jack with external access to a grease fitting provided in a drive nut
Prior Art
Prior art jack designs typically require either partial disassembly of the jack in order to access parts for lubrication, or they attempt to provide grease fittings in proximity to a jack drive nut.
For example, U.S. Pat. No. 6,926,261 to Renshaw describes a trailer tongue jack includes a grease (or zerk) fitting for providing grease to internal parts The jack includes an outer tube and an inner telescoping tube. A threaded insert (or nut) is fixedly attached inside an upper end of the inner telescoping tube. A screw shaft threadedly cooperates with the insert to extend or retract the inner telescoping tube from a lower end of the outer tube. A crank or motor gear assembly is provided to turn the screw shaft either directly or through gears, and a thrust bearing carries a vertical load between the screw shaft and the outer tube.